1. Field of the Invention
The present invention is generally directed to stress wave analysis and particularly to the use and analysis of stress waves to detect foreign object damage (FOD) in turbine engines; such as, but not limited to, jet aircraft.
2. Description of Related Art
Foreign object damage (xe2x80x9cFODxe2x80x9d) has always been a major concern of turbine engine manufacturers and users. Damaged fan, compressor and turbine blades in an engine can result in catastrophic failure or a loss of operating efficiency. To prevent FOD, some turbine systems use filters. However, this is not practical in all cases, due to size, weight, and performance issues created by filters. In non-filtered systems, periodic manual inspection is used to detect any damage at an unknown time after-the FOD event. This unknown leaves a window for the damage to propagate into a catastrophic failure that would endanger lives and/or equipment. Also, manually inspecting all, the blades is a time consuming and costly process. Accordingly, what is needed in the art is a system for detecting foreign object damage to equipment, such as turbine engines, which detects the damage in a timely and cost effective manner. It is therefore to the effective resolution of the shortcomings of the prior art that the present invention is directed.
The present invention provides a FOD detection system consisting of at least one and preferably a plurality of stress wave sensors mounted on an engine at locations that provide transmission path from the fan bearing housing(s), a cable to interface the sensor(s) with the electronics, and an electronic assembly. The electronic assembly conditions the received signal, demodulates the sigrialds and processes the signal to determine/notify if a FOD event occurred. The sensors are preferably externally mounted to the engine. Thus, by using multiple sensors located along the length of the engine, the system can detect the depth that an object has traveled into the engine before the object was destroyed
Accordingly, the present invention provides for the detection of a slow energy event in an extremely high energy environment, without the need of a highly trained professional to analyze data, and also gives a real time indication that a FOD event has occurred. The use of the present invention with a turbine engine should increase the safety efficiency and reliability of such engine.
Accordingly, it is an object of the present invention to provide a system for detecting and analyzing foreign object damage to a piece of equipment or machinery such as a turbine engine.
It is another object of the present invention to provide a system for detecting and analyzing foreign object damage in a relatively timely and cost efficient manner.
It is still another object of the invention to use stress wave signals to detect foreign object damage in a turbine engine.
It is even still another object of the present invention to reduce damage to turbine engines from ingestion of foreign object(s).
It is yet another object of the present invention to improve the reliability of turbine engines.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings.